<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="https://cdn.staticfile.net/font-awesome/4.7.0/css/font-awesome.css">
</head>
<ul class="ul">
    <li>1</li>
    <li class="B">2</li>
    <li>3</li>
    <li>4</li>
    <li>5</li>
    <li>6</li>
</ul>
<div style="width: 100%; height: 50px;background-color: rgb(191, 197, 202);">
    <div class="chang">
    </div>
</div>
    <body>
    <style>
        .chang{
            width: 50%;
            height: 50px;
            background-color: rgb(21, 236, 57);
        }
        .chang:hover{
            animation-name: chang;
            animation: chang 10s;
            position: relative;
        }
        @keyframes chang{
                0%{
                    width: 1%;
                }
                100%{
                    background-color: blue;
                }
        }
        .B{
            background-color: rgb(196, 205, 205);
        }
        .ul :hover{
            background-color:rgb(16, 243, 167) ;
            color: rgb(232, 13, 90);position: ;
        }
        .ul{
            display: flex;
        }
        .ul li{
            list-style: none;
            width: 50px;
            height: 50px;
            border: 1px solid green;
            text-align: center;
            line-height: 50px;
        }
 </style>
</body>
</html>